Liquid Metal-Enhanced PVA-ANF/MXene Hydrogels for Electromagnetic Shielding and Sensing

With the further advancement of communication technology and wearable devices, it is imperative to develop multifunctional electromagnetic shielding materials. In this context, we propose a feasible approach to construct liquid metal-enhanced poly(vinyl alcohol) (PVA)-aramid nanofiber (ANF)/MXene hydrogels for electromagnetic shielding and sensing. By leveraging the excellent conductivity of MXene nanosheets, we successfully prepared three-dimensional flexible PVA-ANF/MXene@Ga hydrogels (PAMG) through the three-dimensional network structure of PVA hydrogels and the mechanical reinforcement of ANFs. With the phenomenon of charge polarization relaxation, multiple interfaces are formed among MXene@Ga, ANFs, and PVA, thus enhancing the mechanical properties and electromagnetic shielding efficiency of the hydrogels. The PAMG hydrogels exhibit an electromagnetic shielding effectiveness of 35.7 dB and a higher water retention capability (with water retention exceeding 60% after 28 days). Furthermore, the hydrogels demonstrate outstanding sensing performance and exhibit high stability for a wide range of human motion detection signals. The research findings indicate that the MXene nanosheet-based electromagnetic shielding hydrogel holds great potential as an ideal platform for multifunctional electromagnetic shielding materials.